Portable vacuum cleaner



FIG. 1 is a top, front and right side perspective view of a portable vacuum cleaner showing my new design;

FIG. 2 is a bottom, rear and left side perspective view thereof;

FIG. 3 is a right side perspective view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and

FIG. 6 is a front elevational view thereof. 

The ornamental design for a portable vacuum cleaner, as shown and described. 